Bill Campbell was mayor of Atlanta in 1996 when a pipe bomb exploded in Centennial Olympic Park. Campbell said he had a horrible sense of deja vu when he heard about the bombings in Boston.

"It really gives me chills just to reflect back. I was at home. I got a call almost immediately from Chief Beverly Harvard that there was an explosion," said Campbell.

An explosion rocked Centennial Olympic Park on July 27, 1996. The park was packed with spectators and athletes in Atlanta for the start of the Olympic games.

"I am stunned that there has not been more of a sense of correlation between what happened in Atlanta - a major sporting event, a backpack they say there were ball bearings used in Boston, there were nails used here," said Campbell.

Eric Rudolph pleaded guilty to detonating that bomb that killed one woman and injured 111 people. He also pleaded guilty to setting off a bomb outside an abortion clinic in downtown Birmingham in 1998.

Rudolph was on the run for more than five years before being captured in Murphy, N.C., in 2003.

A statue, which Mayor Campbell said was a gift to the city for hosting the Olympic games, still sits in the park and bears imprints from nails ejected from the pipe bomb.

"It was a gift from the Greek people. It ended up deflecting some of the nails that were placed in the pipe bomb by Eric Rudolph and ended up help to preserve life here in Atlanta," said Campbell.

Investigators initially focused their attention on security guard Richard Jewell, who turned out to be a hero. He spotted the backpack, as authorities were evacuating the park, the bomb exploded.

Campbell doesn't believe investigators in Boston will make the same mistake.

"The Atlanta investigation was a difficult one because, remember what's different from Boston is that the marathon was over, but the Olympic games here were just beginning," said Campbell.

Dale Earnhardt Jr. smiles at members of various sports teams from his former high school during a news conference after practice for the NASCAR Cup Series auto race at Charlotte Motor Speedway in Concord, N.C., Friday, Oct. 6. (AP Photo/Chuck Burton)

Dale Earnhardt Jr. announced on Instagram on Monday afternoon that he and his wife, Amy, are expecting their first child soon.